I'm building a 1982 351 windsor for my 87 f150 and I had a few questions and wanted some opinions on some things... so far I bought a edelbrock performer series intake and I will be running a quadrajet.. are there any special modifications I should do other make this carb better off road? I was going to port and polish the heads the best I could by myself... is this worth doing? Will I see any power gains? I will be putting a new cam in the engine also and was looking at one of the comp cams extreme 4x4 ones... are these any good? If so which one would u recommend? What makes one better than the other? And I'll also be rebuilding the engine since it is all apart... I guess you could call this a mild build and I wI'll be doing moderate off roading with the truck and farm workand I want the engine to be able to handle it... does anyone know with what I'm doing with the engine around how much horsepower and torque I'll expect to see? Thanks

 

Don't waste a second of your time or spend a dime on the stock heads.. they are junk. Instead go get a set of GT40's off an Explorer 5.0 and freshen them up. When rebuilding the bottom end install cast or hyper flattop pistons with valve eyebrows and all new bearings once the castings have been returned to spec at a machine shop, and use a regular volume oil pump not a high volume. When picking a cam keep in mind that even with the better heads this motor will still only make power up to about 4500rpm so the cam should match that.

 

Do the GT40's just bolt right to the 351? Or do I have to drill the bolt holes out?

 

Is there anything I could do to make the stock 351 heads better or are they just plain junk? Also are 351 cleveland heads better than GT40's on this motor? Will the intake I already have for the stock heads fit with gt40 heads? What about my headers?

 

Most GT40 heads you find will bolt right on, some will need to have the bolt holes drilled out.. but that is not a big deal.

Stock heads have hugh smog era combustion chambers and flow very poorly.. they are complete junk. GT40s flow at least 25% better and have larger valves and smaller chambers.

You can't bolt Cleveland heads on this motor without a special(read expensive) intake.

The intake you have will work with GT40s and any standard header for a 351 in this truck will still work.

 

Thank you this helped alot.. what year motor should I look for gt40 heads off of? I cold probably get them fairly cheap out of a junkyard... are these the only heads that aren't aftermarket that will fit on a 351w? Are they the best choice? Also, should I look to get gt40p heads or just gt40 heads???

 

The GT40 and GT40P heads are the best non aftermarket heads available for these motors, the p version actually flows a little better again but the radical plug angle makes fitting headers more of a challenge. GT40s were found on all 96-97.5 Explorer/Mountaineer 5.0 motors, all Gen1 5.8 Lightnings, and 93-95 Mustang Cobras.

Late model E7TE heads would also bolt on and boost CR about 1/2 a point from the smog heads but they don't flow significantly better.

 

Looks like I'll probably be taking a trip to the u pull it yard here soon to get some gt40 heads... they will probably be easier/cheaper since the explorers were more plentiful than the lightnings and cobras right? Especially in a junkyard I would think... but one more question.. are 351w heads from a 72 to 78 f250 any good? Better than GT40's or gt40p?

 

Nope, they have similar valve sizes and small combustion chambers but they are from the leaded gas era so they don't have hardened valve seats and the ports design isn't quite as good.

 

Ok thanks... do u know if many lightnings are in junkyards? Id like to get a set of GT40's off of one of the 5.8.. I think I read more today about these heads and all the other heads than i have in all 15 years of my life

 

Lightnings are highly sought after and coveted by many. Highly doubt you would ever find one in a junkyard. Explorers were very plentiful and much easier to find with GT40 heads still in place. As previously noted GT40s from a 5.0L engine will require drilling out the head bolt holes to work on a 5.8L engine.

 

That's what I figured buy was hoping maybe a wrecked one would be there. Did explorers with a 351 have gt40 heads?

 

The Explorer never left the factory with a 351/5.8L engine. The biggest was the 5.0L.

 

Ok thanks... should I look for 351 lighting heads or are the 302 explorer/mountanier heads just as good

 

The heads on these two motors are exactly the same.